Advances in photolithographic techniques and other fabricating methods have permitted the manufacture of very small scale fluidic mechanisms on silicon chips. Perhaps the best-known example is the inkjet printhead die, which has revolutionized desktop publishing by permitting the manufacture of desktop printers that can produce documents with both a high level of detail, and precise control of color.
Unfortunately, as printheads are manufactured to ever smaller dimensions and closer tolerances, the ink delivery system must still deliver fluid consistently and cleanly from the ink supply (a macrosopic fluidic system) to the printhead die (a microscopic fluidic system).
Although manifold structures may be prepared using low cost molded plastic, such molded manifold structures typically cannot attain the geometries required by printhead dies with ever-decreasing feature sizes. This is particularly true as the overall size of the manifold parts increase for supplying ink to large printhead arrays. Molded plastic parts also do not lend themselves readily to secondary machining operations for improved flatness. Although parts may be prepared via die casting or other molding processes, the resulting manifold structures similarly have difficulty in creating sufficiently small geometries or the kinds of feature sizes required for larger parts.
The use of photolithography or laser etching may produce very fine feature structure, but such fabrication methods may be prohibitively expensive. While they may reach the required dimensions, fabrication methods are typically too costly either due to the materials used, the processing time, the capital investment required, or some combination of the three.